The air quality in Delhi remained in the “very poor” category on Tuesday morning, a day after many residents of the national capital defied a ban on firecrackers.

Data at 9.23 am on System of Air Quality and Weather Forecasting And Research, or Safar, showed that Delhi’s Air Quality Index, or AQI, stood at 323. This indicates “very poor” conditions that pose a risk of respiratory problems on prolonged exposure.

The air quality index deteriorated from 312 on Monday evening, according to Central Pollution Control Board data.

While bursting firecrackers have become a norm during Diwali, Delhi authorities in September had imposed a ban on their sale, use and production till January 1 to prevent the city’s air quality from worsening in winter.

Last week, Delhi Environment Minister Gopal Rai had said that those caught setting off firecrackers this time would be punished with a fine of Rs 200 and jail term of six months.

However, as dusk fell on Monday, residents began bursting the firecrackers despite the ban and penalty. High-intensity firecrackers could be heard going off on the ground or mid-air in several areas of the city such as East of Kailash, Nehru Place, Moolchand, Laxmi Nagar, Mayur Vihar, Shahdara and Burari.

Bhartiya Janata Party leaders claim that the ban is Arvind Kejriwal-led government’s attempt to curb the Hindu tradition of bursting firecrackers on Diwali.

As Delhi residents defied the ban again this year, Amit Malviya, who is the head of BJP’s information and technology department, noted in a tweet that Rai had threatened to put those bursting firecrackers in jail.

“Where is Kejriwal who was trying to do such audacity with Hindus?” he asked, along with a video of firecrackers lighting up the Delhi sky. “Is there any prison that can accommodate so many people?”

Malviya also cited data of stubble burning – another factor that contributes to Delhi’s pollution in Diwali – showing that Punjab had the highest number of farm fire instances among the states neighbouring the national capital.

Punjab, which is also governed by the Aam Aadmi Party, had 1,019 instances of stubble burning on Monday, followed by 250 in Haryana and 215 in Uttar Pradesh, according to data shared by the BJP leader.

“1,019 instances of farm fires in AAP run Punjab on the day of Diwali is the reason for poor air quality in not just Delhi but whole of north India,” he wrote on Twitter.

Delhi pollution

Farmers from Punjab, Haryana and Uttar Pradesh burn the residue of their paddy harvest during this season since it is a cost-effective and time-saving measure to prepare the fields for the next sowing cycle. However, this practice results in increased levels of air pollution in large areas of North India.

Lower temperatures, wind speeds, and other factors such as industrial pollution add to the problem. Often, the AQI drops around Diwali, when firecrackers are burst.

Due to this, Delhi has been ranked as one of the most polluted cities in the world. In 2020, New Delhi’s average annual concentration of PM2.5 – particulate matter with a diameter of less than 2.5 micrometres – per cubic meter of air was 84.1, a study said, making it the 10th most polluted city in the world.

Particulate matter smaller than 2.5 microns (or about a ten-thousandth of an inch) is particularly dangerous to human health. Such particles are small enough to travel deep into the respiratory system, potentially impairing lung function.

Despite the ban on firecrackers, Delhi’s air quality index in November last year was the worst since 2015.